.

^18. Frank B. Salisbury et al., “Bios-3: Siberian Experiments in Bioregenerative Life Support,” BioScience, vol. 47 (1997): 575–585.

^19. John Allen has written an autobiography: John Allen, Me and the Biospheres, Synergetic Press, Santa Fe, NM, 2009.

^20. John Allen et al., “The Legacy of Biosphere 2 for the study of Biospherics and closed ecological systems,” Advances in Space Research, vol. 31, no. 7 (2003):1629–1639.

^21. Personal communication with John Allen.

^22. Most of the key published papers are available at www.globalecotechnics.com. Elsevier special edition: Biosphere 2 Research Past and Present, eds.. B.D.V. Marino, H.T. Odum, Ecological Engineering Special Issue, Vol. 13, Nos. 1-4, Elsevier Science, 1999.

^23. http://wordlesstech.com/2013/11/26/tomato-space/

      TWO The Long March

      IN JANUARY 2013, American biologist and author Paul Salopek set off to trek around the world. He began his journey at a lake in the Great Rift Valley of Ethiopia, where remains suggest that modern man originated. Salopek’s goal, over a period of seven years, is to walk all the way to Tierra del Fuego— a region that lies the furthest from humanity’s birthplace—via the Middle East, Southeast Asia, China and North America. His planned hike is about 30,000 kilometers long (21,000 miles); he hopes to complete it in 2020. Salopek wants to retrace the path that humans have taken since starting out from Africa.

Before humans came on the scene, many animal species had already spread across the earth’s surface. Humans, however, were the start of something quite new. The biggest difference between us and other members of the Club of Revolutionaries such as cyanobacteria or algae is that we are able to act consciously with the help of a molecular electronic mirror image of ourselves and the world.²⁴ This difference, our uniquely precious ability, is what makes the Anthropocene completely new: human consciousness and geology forming a unity. By rights, there should be a UNESCO world cultural heritage site in East Africa named “The Origins of the Human Consciousness,” where Salopek’s journey started. The dimensions of this evolutionary event are simply colossal, extending from the first groups of humans who used pronouns like I, you and we, to online social networks connecting billions of people. They link the earliest humans who looked in awe at the sky to the builders of the Hubble Space Telescope, and the first stone tools to quantum computers of the near future.

      Part of our emerging consciousness is an ever increasing awareness of our long march, how deeply rooted we are in the cosmos, the solar system, our planet and life. This awareness is not always present in our everyday lives, what with washing dirty dishes, chatting on social networks, or meeting deadlines. Part of the appeal and beauty of scientific research is to develop this awareness more thoroughly in ever greater detail.

Humans are the way we are because water, carbon, oxygen, minerals and metals were distributed across earth from the beginning in very specific proportions. We are the result of hundreds of millions of years of evolution, from individual unicellular organisms that began to cooperate, to the estimated 37 trillion cells combining to assemble organs as complex as the human brain.²⁵

Not only every stone but every person encapsulates the entire history of life and the universe.²⁶ The atoms making up our bodies have been traveling through the cosmos for billions of years. Each atom in our bodies has already served to build hundreds of other life forms before us; perhaps it swam in a fish long before humans appeared or lay deep in the soil or was a building block in a bacterium. Our bodies are gigantic zoos of evolutionary history. Hundreds of millions of years of evolution has shaped the way we think and perceive, from the first four-celled organisms with nerve endings on to fish, and from there to the first four-legged animals to primeval mouse-like mammals, on to the first primates who developed into early humans. After millions of years, a species of thinking, humanoid life forms rose to the challenge of survival in the vastness of Africa and developed characteristics similar to what we humans have today.

      Modern-day people have brains that have been transformed by environment, long before people acquired the ability to change the environment. Nowadays, what we like or dislike, or fear or do not fear, or perceive to be or not, have much to do with the living conditions of our ancestors. These forebears include the squirrel-like Purgatorius that lived soon after the extinction of the dinosaurs; Eosimias, one of the earliest anthropoids that lived 41 million years ago; the chimpanzee-sized Kamoyapithecus that lived 25 million years ago, regarded by many researchers as the first hominoid and the last mutual ancestor before chimpanzees, that lived in Africa approximately 7 million years ago. This leads finally to the first hominids such as Sahelanthropus and Australopithecus that paved the evolutionary path for the genus Homo. Our lives today are linked by invisible threads to this past; each set of respective environmental circumstances, from the meteorite impact that doomed the dinosaurs, allowing for the era of mammals (who could otherwise have become the pets of highly intelligent dinosaur descendants) to the expansion of the savannah in East Africa due to natural climate change.

Besides our consciousness, what makes us humans uniquely able to create the Anthropocene, is our incredible generalism, that is, our ability to adapt not only to new circumstances but also to be the shapers of our habitat.²⁷

      Our biological constitution is, for the most part, an echo from the past three million years when the earth was significantly colder than it is today. A factor that contributed to this cooling process was the formation of the Isthmus of Panama three million years ago, which connected North and South America and interrupted the flow of warm water from the Pacific Ocean over to Africa. Atlantic currents were forced northwards, eventually leading to the formation of today’s Gulf Stream. The Himalayan mountain range also continued to rise, which rerouted Asian rivers to flow northward rather than south. Flowing into northern seas diluted their salt concentration: water that is low in salt freezes more quickly, which led to the glaciation of the Arctic region. The sea level sank during these periods to an average of 426 feet because the water froze.

Then the level rose again as subsequent oceanic and atmospheric changes led to warming periods. The Great Rift Valley in East Africa, where early hominids lived, rose slowly but continuously during this epoch, creating a drier habitat and causing forests to change to savannahs—an environment where an upright gait was a significant advantage.²⁸

Early humans lived during times of sweeping change in the natural world that surrounded them. Whereas many species remained unchanged and only reacted to events, our ancestors were more flexible, innovative, and adaptable. Environmental changes even tended to foster flexibility and generalism in early humans. They developed an ability to survive under varied conditions, sustained by a wide variety of foods. The route to today’s world, wherein people can live in Arctic cold or tropical heat, on mountaintops or in river deltas, in Indian slums or in air-conditioned New York stockbrokers’ offices, arose a good two million years ago; omnivorous hominids proving to be very skilled at adapting. Due to genetic changes, brain size increased more rapidly, something